It's really a time factor for you. Not knowing your granny charger output let's go for 2.3 kw. The SR has 50.8kw usable. Allowing for losses it will roughly take about 23 hours 0 to 100%. Looking at you figures you use 100 miles per week which may equate to roughly 29kw using 3.5 miles per kw as a base figure (potentially a lot less in winter). To top up 29kw with 2.3kw is roughly 12 - 15 hours charging. Each day you go 16 miles which will be roughly 5kw. So each day top up could be 2 - 3 hours. You can alter the figures accordingly as city might be 5.2 miles per kw but I hope you can see where I am going. So perhaps nightly top up to a certain % in the settings, such as 80%, may suit you best but it's a horses for courses and down to individual preference. Can you 'steal' power at work, use a nearby Tesco etc. because every little helps keep costs down?
So for example initial charge to 80%, top up to that level nightly. 100 % if you get free charging or twice weekly on your granny plug and then setting to a set % accordingly...whatever you choose. 100% will not really damage the LFP batteries but if you want to be on the safe side 90% is the regular max setting I believe.
My figures are rough and others may disagree but it gives you an insight into charging option
SR published figures
Real Range Estimationbetween 130 - 275 mi
City - Cold Weather * | 180 mi |
Highway - Cold Weather * | 130 mi |
Combined - Cold Weather * | 155 mi |
City - Mild Weather * | 275 mi |
Highway - Mild Weather * | 170 mi |
Combined - Mild Weather * | 215 mi |
Alan